tvrigs.org.uk » Whitby Mudstone

June – Alum Shale

admin — Mon, 01 Jun 2009 07:40:14 +0000

Alum Shale occurs within the upper 35 metres or so of the Whitby Mudstone Formation. A suite of rocks that originated as soft sediment accumulating on the floor of an ancient sea (the Tethys) which occupied this area between c.188 million and c.182 million years ago during the late Lower Jurassic phase of Earth’s geological history.

Alum Shale is an unremarkable, grey, thinly-bedded, pyritic mudrock that weathers readily to thin crumbly flakes, the detritus often forming steep talus slopes below the working faces in numerous alum quarries that today reside peacefully along the coast and hills of Cleveland and North Yorkshire. The quarries and boiling houses operated for over 260 years here, commencing around 1600, in the only district in Britain where rock suitable for the important industry of alum-making was, and still is, able to be extracted.

The Tethys Sea supported a diverse fauna of, now mostly-extinct, creatures amongst which can be counted a wide-range of ammonite species, belemnites, fish, and a number of large reptiles including crocodiles, ichthyosaurs and plesiosaurs. At the end of their lives, the remains of these creatures would settle on the sea-floor and occasionally become buried and preserved as fossils. Given the rock’s mode and time of creation, who amongst us could have imagined that the remains of these leviathans, tokens of antiquity from a long lost world millions of years after their lives had ended, would once again see the light of day by way of a quarryman’s hands.

Ammonites achieved their evolutionary zenith during the Jurassic as a result of which some species are only found within a very small stratigraphic range. The usefulness of this to geologists in ascertaining the relative ages of strata was noticed by alum-maker’s son Louis Hunton (1814-1838), who collected data at coastal quarries and made valuable contributions to the young science of biostratigraphy in the 19th century.

The large reptile fossils began to come to light during the 18th century at a time when the science of geology was in its infancy. They provided some of the earliest, best preserved, fossils to be examined by early palaeontologists and found their way to academic establishments across the world. Specimens of these and many more fossils can be seen today on display in Pannett Park Museum, Whitby.

The image above shows Lower Jurassic Alum Shale (grey) making up the lower part of the cliff at Rosedale Wyke, Port Mulgrave. The overlying yellow-brown sandstone belongs to the Middle Jurassic Saltwick Formation.

November – Ammonite

admin — Sat, 01 Nov 2008 12:39:00 +0000

Ammonites are coiled relatives of the octopus (Cephalopods) and became extinct at the end of the Cretaceous Period around 65 million years ago.

Below is an image of a Harpoceras, which lived during the Jurassic Period. These fossils can be found in the Upper Liassic shale (Whitby Mudstone Formation) which crops-out widely across Cleveland and the Tees Valley. They lived in a warm tropical sea which occupied the area around 185 million years ago, alongside squid-like belemnites, marine crocodiles, ichthyosaurs, and long-necked plesiosaurs all of which have been discovered locally.

Ammonites reached their evolutionary zenith in the Jurassic and a great number of different short-lived forms existed during this Period. This resulted in fossils of each species being distributed in discrete bands within the rock record, a quality which geologists employ in correlating similar rock units across widely seperate districts.

Cass Rock Quarry

admin — Sat, 20 Sep 2003 17:30:07 +0000

Contents

Site Description
Site Map
Summary Evaluation of Site’s Value and Importance
Surveyors

Grid Reference NZ 631 146
BGS Sheet 34
OS Sheet 94
Forwarded as RIGS Part of Guisborough Forest 30/09/2003

Site Description

Site Status SNCI

Brief Site Description Site 7 of 7. Disused alum quarry revealing exposures of Liassic Whitby mudstone and overlying Middle Jurassic Saltwick sandstone. Following abandonment after alum working, this quarry was used as a dump for ironstone spoil from mines around Slapewath. Shale was transported via an aerial ropeway.

Literature References Guisborough District Mines – Simon Chapman 2001

Site Map

Summary Evaluation of Site’s Value and Importance

Scientific Value
The sites in this group exhibit diverse examples of Liassic (Lower Jurassic) and Middle Jurassic deltaic deposits along with industrial archaeological remains.

Historical Value
Various industrial archaeological remains at the seven sites including ironstone extraction, the earliest alum quarries in England, and nineteenth century jet mining. Cass Rock Quarry was worked for alum shale between 1776 and 1805.

Aesthetic Value
From its vantage point high on the escarpment of the Cleveland Hills, Cass Rock Quarry provides an ideal vantage point giving commanding views of East Cleveland and the coast.

Educational Value
Situated beside the Cleveland Way to the east of Guisbrough Forest, Cass Rock is potentially a good site at which to examine Upper Liassic shales, Middle Jurassic sandstone, and explore the site of a former alum quarry. Nature has reclaimed this quarry and care should be exercised around vertical faces.

Surveyors

Andrew Carter, John Waring

Easington Beck

admin — Thu, 04 Sep 2003 17:09:05 +0000

Contents

Site Description
Site Map
Site Assessment
Surveyors

Grid Reference NZ 749 162
BGS Sheet 34
OS Sheet 94
Forwarded as RIGS 30/09/2003

Site Description

Site Status SNCI
Description of Geodiversity Upland river cutting through deltaic sandstone revealing river-cliffs and waterfalls. Exposures include Saltwick sandstone, Dogger and Whitby mudstone formations
Literature References

Site Map

Site Assessment

Access and Safety	Comments	Rating
Safety of access	From footbridge and along stream bank	8
Safety of exposure	Slippery on waterfall features and 6m vertical drop	4
Restricting conditions	High flow episodes and adverse weather	5
Multiple exposure	Reach of Easington Beck	10
Note	It is strongly suggested that on-site safety be the responsibility of the party leader(s), as the safety information above is given only as a guide.

Education and Science	Comments	Rating
Surface processes	Various fluvial processes	10
Geomorphology	V-shaped valley upstream, downstream examples of river gorges and waterfalls	10
Sedimentary rock	Lias and Ravenscar groups (including rare Dogger exposure below the Saltwick formation)	10
Igneous rock	Glacial erratics in stream bed	2
Metamorphic rock	Glacial erratics in stream bed	2
Fossils	Various trace fossils throughout river reach	5
Minerals	Tufa (including stalactites), Calcite and Iron oxide weathering	8
Structural features	Various examples of faulting through river reach	5
Stratigraphy	Sheet jointing in Eller Beck formation	5

Geodiversity Value	Comments	Rating
Education	Excellent for fluvial processes but very difficult access	8
Scientific	Site of special interest for Earth scientists	10
Historical	None
Aesthetic	Excellent fluvial environment in wooded steep sided gorge	10

Surveyors

Andrew Carter, Andrew Cooper, Carl Rees-Davies

Hell Gill

admin — Fri, 01 Aug 2003 17:45:28 +0000

Contents

Site Description
Site Map
Site Assessment
Surveyors

Grid Reference NZ 599 131
BGS Sheet 34
OS Sheet 93
Forwarded as RIGS Part of Guisborough Forest 30/09/2003

Site Description

Site Status SNCI
Description of Geodiversity Late glacial V-shaped valley. Exposure of Cleveland ironstone (Pecten seam) along roadside. Further along track spoil tips of Whitby mudstone (Jet shale member) can be observed
Literature References Glimpses of Monument Mine, Great Ayton – Richard Pepper 1996

Site Map

Site Assessment

Access and Safety	Comments	Rating
Safety of access	Via public footpath and forest tracks from Hutton Village	10
Safety of exposure	View from forest track	10
Restricting conditions	Forestry work	8
Multiple exposure	With Bold Venture Gill, Hill Plain, and High Cliff Nab along track	10
Note	It is strongly suggested that on-site safety be the responsibility of the party leader(s), as the safety information above is given only as a guide.

Education and Science	Comments	Rating
Surface processes	Weathering and erosion	8
Geomorphology	Late glacial V-shaped valley on escarpment	8
Sedimentary rock	Ironstone with inter-bedded mudstone, also Alum and Jet mining spoil	10
Igneous rock	None
Metamorphic rock	None
Fossils	Various marine	7
Minerals	Siderite and Calcite	8
Structural features	None specific	2
Stratigraphy	Cleveland ironstone (Pecten seam)	10

Geodiversity Value	Comments	Rating
Education	Fossil identification	10
Scientific	Study by Earth scientists	10
Historical	Jet shale mining	8
Aesthetic	Area of forestry, rough exposures and spoil	6

Surveyors

Denis Goldring

Belmont Bank

admin — Fri, 01 Aug 2003 16:59:23 +0000

Contents

Site Description
Site Map
Site Assessment
Surveyors

Grid Reference NZ 622 148
BGS Sheet 34
OS Sheet 94
Forwarded as RIGS Part of Guisborough Forest 30/09/2003

Site Description

Site Status SNCI
Description of Geodiversity North facing escarpment revealing few exposures. Underlying geology is Staithes sandstone, Cleveland ironstone, Whitby mudstone overlain by the Saltwick sandstone formation. Old mine tips now wooded
Literature References Guisborough District Mines – Simon Chapman 2001
The Floating Egg – Roger Osbourne 1998

Site Map

Site Assessment

Access and Safety	Comments	Rating
Safety of access	Via Belman Gate up footpath	10
Safety of exposure	Safe footpath	10
Restricting conditions	None
Multiple exposure	Various exposure in Guisborough Forest	10
Note	It is strongly suggested that on-site safety be the responsibility of the party leader(s), as the safety information above is given only as a guide.

Education and Science	Comments	Rating
Surface processes	None observable
Geomorphology	Glacial features	7
Sedimentary rock	Poor exposures	3
Igneous rock	None
Metamorphic rock	None
Fossils	None specific due poor exposures
Minerals	None specific
Structural features	None specific due poor exposures
Stratigraphy	None specific due poor exposures

Geodiversity Value	Comments	Rating
Education	Limited educational value	2
Scientific	Limited due to poor exposures	2
Historical	Early Alum quarry dating back to seventeenth century. More recently ironstone mining (Belmont mine) can be observed	10
Aesthetic	Wooded escarpment	10

Surveyors

Denis Goldring

Boulby Quarry

admin — Tue, 01 Jul 2003 19:02:48 +0000

Contents

Site Description
Site Map
Site Assessment
Surveyors

Grid Reference NZ 738 200
BGS Sheet 34
OS Sheet 94
Forwarded as RIGS 30/09/2003

Site Description

Site Status SSSI and Part of the Heritage Coast
Description of Geodiversity Extensive disused quarry area revealing workings in the Alum shale member of the Whitby mudstone formation. Top of the quarry reveals exposures of massive Saltwick sandstone with sporadic exposures of the underlying Dogger formation
Literature References Along the Scar – Denis Goldring 2001
Steeped in History – I Miller, North Yorkshire Moors NPA 2002

The Floating Egg – Roger Osbourne 1998

The Regional Coastline of Yorkshire – J.W.Steers 1967

Site Map

Site Assessment

Access and Safety	Comments	Rating
Safety of access	Access along Cleveland Way footpath from Boulby or Upton	10
Safety of exposure	Hazardous cliff edge at the base of quarry and hazardous backwall from the Cleveland Way footpath	4
Restricting conditions	High winds due to hazardous cliffs etc	8
Multiple exposure	From Boulby Quarry along the Cleveland Way to Loftus Quarry and Hummersea	10
Note	It is strongly suggested that on-site safety be the responsibility of the party leader(s), as the safety information above is given only as a guide.

Education and Science	Comments	Rating
Surface processes	Weathering, erosion and transportation	10
Geomorphology	Cliffs and talus slopes	10
Sedimentary rock	Lias sequence specifically the Whitby mudstone & Saltwick sandstone formations. The rare Dogger formation is exposed at some points below the Saltwick	10
Igneous rock	None
Metamorphic rock	None
Fossils	Various marine in the Whitby mudstone	10
Minerals	Pyrite oxidation	3
Structural features	Shallow dipping strata	3
Stratigraphy	Exposures of upper Lias and lower Ravenscar groups	10

Geodiversity Value	Comments	Rating
Education	Basic geology study and fossil collection	10
Scientific	Special site for study by Earth scientists	10
Historical	Disused site of major Alum mining area with some associated mining structures and features	10
Aesthetic	Coastal cliff feature	10

Surveyors

Denis Goldring

Rock Hole Quarry

admin — Tue, 13 May 2003 10:23:26 +0000

Contents

Site Description
Site Map
Site Assessment
Surveyors

Grid Reference NZ 641 160
BGS Sheet 34
OS Sheet 94
Forwarded as RIGS 30/09/03

Site Description

Site Status
Description of Geodiversity Disused Alum quarry environment revealing exposures of Alum and Jet shales of the Whitby mudstone formation.
Literature References

Site Map

Site Assessment

Access and Safety	Comments	Rating
Safety of access	Via the Cleveland Way footpath	10
Safety of exposure	Safe quarry environment except scree slopes	9
Restricting conditions	None
Multiple exposure	Slapewath locality	10
Note	It is strongly suggested that on-site safety be the responsibility of the party leader(s), as the safety information above is given only as a guide.

Education and Science	Comments	Rating
Surface processes	Weathering, erosion and transportation	8
Geomorphology	Mini cliff and talus slopes examples	8
Sedimentary rock	Whitby mudstone formation (Jet and Alum shale members)	10
Igneous rock	None
Metamorphic rock	None
Fossils	Various marine	8
Minerals	Calcite and Sulphur	5
Structural features	Minor folding	5
Stratigraphy	Jet and Alum shale members exposed	8

Geodiversity Value	Comments	Rating
Education	Fossil identification and geomorphology study	8
Scientific	Study by Earth scientists	8
Historical	Disused Alum shale quarry	8
Aesthetic	Imposing quarry feature	5

Surveyors

Andrew Carter, John Waring

Bold Venture Gill

admin — Thu, 17 Apr 2003 19:22:18 +0000

Contents

Site Description
Site Map
Site Assessment
Surveyors

Grid Reference NZ 603 133
BGS Sheet 34
OS Sheet 94
Forwarded as RIGS Part of Guisborough Forest 30/09/2003

Site Description

Site Status SNCI and RIGS
Description of Geodiversity Old quarry area revealing Jet shale sequence of the Whitby mudstone formation
Literature References Guisborough District Mines – Simon Chapman 2001
The Floating Egg – Roger Osbourne 1998

Site Map

Site Assessment

Access and Safety	Comments	Rating
Safety of access	Via forestry track from Hutton Village	10
Safety of exposure	Dangerous talus slope in wet conditions	5
Restricting conditions	Forestry work	8
Multiple exposure	Hill Plain and Hell Gill along track	10
Note	It is strongly suggested that on-site safety be the responsibility of the party leader(s), as the safety information above is given only as a guide.

Education and Science	Comments	Rating
Surface processes	Weathering and erosion	10
Geomorphology	Cliff and talus slope example	8
Sedimentary rock	Whitby mudstone - Jet shale sequence	10
Igneous rock	None
Metamorphic rock	None
Fossils	Various marine throughout	10
Minerals	Calcite, Sulphur and Limonite	8
Structural features	Vertical faulting	5
Stratigraphy	Single sequence of Jet shale	2

Geodiversity Value	Comments	Rating
Education	Geomorphological study	8
Scientific	Study by Earth scientists	10
Historical	Disused Jet shale quarries	5
Aesthetic	Escarpments of Bold Venture Gill	10

Surveyors

Andrew Carter, John Hempson